CELINA — A nationwide manhunt is underway for a 40-year-old man believed to be responsible for the shooting death of a Rockford woman on Thursday.

An arrest warrant has been issued for Daniel C. Martin, 40, for murder. Mercer County law enforcement officials believe Martin played a role in the shooting death of Melinda S. Shinn, 26, inside her residence at 509 North St., Rockford. Martin was Shinn’s boyfriend at the time of the shooting. Martin’s red Ford Explorer was located in Fort Wayne, Ind., but he remains at-large as of press time.

“We have other law enforcement agencies trying to help us locate him,” Mercer County Sheriff Jeff Grey said during a news conference Friday morning. “This is the kind of crime where we will go any place in the country to get him. We would also go to foreign countries — if he went to Canada — to get him.”

Mercer County Dispatchers received a phone call at 10:43 a.m. Thursday regarding the shooting. Rockford Police Chief Paul May entered the home and found Shinn dead. May asked the Mercer County Sheriff’s Office to assist in the investigation. The Ohio Bureau of Criminal Investigation also was called in to help process the crime scene.

Grey said shortly after investigators arrived on the scene, deputies obtained a search warrant for the residence and were able to recover evidence from the scene. An autopsy also was ordered to determine the exact cause of death.

Several potential witnesses also were interviewed on Thursday. Following those interviews, Grey said an arrest warrant was issued for Martin at 5 p.m. Thursday.

More details in the shooting emerged during Friday’s news conference. Grey revealed Shinn’s 9-year-old son was in the home at the time of the shooting. However, investigators declined to say if the boy — who is not Martin’s son — witnessed the actual shooting. They did note the boy is safe and with relatives.

Grey also cautioned the public against approaching Martin if they spot him.

“We do believe that he is currently still armed, so we would suggest to the public if you see him, call your local law enforcement agency,” Grey said. “We do not know what he is capable of. At this point, I am sure he’s scared and he knows we are looking for him.”

Martin has a long criminal record. Grey said Martin has faced charges including carrying a weapon without a permit.

“He’s known to have some violent tendencies,” Grey said.

Shinn and Martin were believed to have engaged in a series of arguments Wednesday night and into Thursday morning. That information, Grey noted, was verified through a series of text messages reportedly sent from Shinn to people outside the home. Grey said it is believed Martin shot Shinn early Thursday morning inside the residence. Grey declined to reveal where Shinn’s body was found inside the home.

“The whole incident occurred inside the mobile home,” Grey said.

Deputies were familiar with the residence. Grey said his office handled a few calls that involved arguments. May said his department handled similar calls.

The homicide is the first in Rockford.

“We’ve never had an incident like this in the village of Rockford,” May said. “I’ve been here for 20 years.”

While Martin’s vehicle was recovered in Fort Wayne, Grey declined to speculate if investigators believed Martin was in the city.

“We don’t know for sure right now,” Grey told The Evening Leader. “We are trying to track him down right now and talk to anyone who may know his whereabouts.”

He also declined to reveal if investigators have spoken with Martin’s family in Fort Wayne.

Rockford Mayor Amy Joseph said the village of 1,120 residents is still shock regarding Shinn’s death.

“This is something that does not happen in our village,” Joseph told The Evening Leader. “I’ve been assured by the sheriff’s office and Chief May that this wasn’t just a random thing, that it was between two people, and that the village should feel safe and not have anything to worry about.”

May said he knew Shinn and her son. May coached the boy in football this year.

“I knew her and I knew her son,” May said. “It’s very hard. We just don’t expect that in our area.”

The homicide is the third in Mercer County in less than 12 months. Robert Grube and his daughter Colleen Grube were killed in a rural Fort Recovery residence on Nov. 30, 2011. That case remains unsolved at this time.

Anyone with information regarding Martin’s whereabouts is encouraged to call the Mercer County Sheriff’s Office at 419-586-7724.